It is known that serotonin could modulate response to stress, and therefore, the availability of its transporter could be influencing mechanisms as resilience (Feder et al., 2009[16]). Mixed results have been observed between 5-HTTLPR and resilience, since both alleles, S and L, have been associated with differences in its levels. For example, in a previous study (Stein et al., 2019[43]), S carriers had a lower level of resilience. In contrast, in individuals with a high exposition to childhood traumas, the resilience levels were lower in L carriers (Carli et al., 2011[7]), and other studies have not found significant associations (O'Hara et al., 2012[34]). In this work, we aimed to perform a meta-analysis in order to clarify the effect of 5-HTTLPR on resilience levels in humans.